Question

A sphere of iron and another of wood, both of same radius are placed on the surface of water. State which of the two will sink? Give reason to your answer.

March 17, 2024

Answer

When a sphere of iron and wood are placed in water then the sphere of iron will sink.

The reason is that ρ_iron > ρ_water, so the weight of iron sphere will be more than upthrust due to water on it. But ρ_wood < ρ_water, so sphere of wood will float will it’s that much volume submerged inside water by which upthrust due to water on it balances it’s weight.

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